Gas-tight seal for boxcar outlets



Sept. 29, 1959 I. CRUMLEY ET AL 2,

GASTIGHT SEAL FOR BOXCAR OUTLETS Filed Oct. 14, 1957 um. 1| l luumumu "WWIIHHIHIIII| 29 E INVENTORS.

Lam 0 hm Gel/Amer v BY ROBERT 64km. Fau'o/v GAS-TIGHT SEAL FOR BOXCAR OUTLETS Lloyd Ira Crumley, Fredonia, Kans., and Robert Carroll Fulton, Kansas City, Mo., assignors to Archer-Daniels- Midland Company, Minneapolis, Minn., a corporation of Delaware 1 Application October 14, 1957, Serial No. 620,124 1 Claim. or. Mil- 380) This invention relates to a novel seal for a container opening and more particularly, for rendering boxcar outlets gas-tight during transportation of the product contained therein.

In the handling of alfalfa and other forage crops it is extremely important to preserve the carotene (pro-vitamin A) content or activity thereof from the time the same is initially harvested and throughout all processing and handling operations, until placed in use by the ultimate consumer. A large percentage of such crops is today placed in pellet form prior to shipment and storage and it is quite common to immediately place the pellets ,in storage within an inert gas such as carbondioxide after the container has been purged of its oxygen content inasmuch as the aforementioned vitamin and carotene content is not appreciably reduced over a long period of time as long as the air is kept therefrom.

Many of the problems incident to such operations have been met in recent years with respect to storage in stationary containers, but no satisfactory means has heretofore been provided to maintain the products within the inert gas conditions during shipment. It is pro-posed to transport the same by rail and it is, of course, possible to construct boxcars or the like which are substantially impervious to gas escape, but the expense is not warranted if the mobile unit is to be used only for such single.

purpose. Therefore, the railway companies generally prefer to use existing equipment and to modify the same as inexpensively as possible to permit the hauling of the pellets while subjected to the carbon dioxide or the like.

It is the primary object of the instant invention, therefore, to provide structure that will make it possible to use present-day boxcars in the transportation of alfalfa pellets or the like while subjected to the inert gas.

Conventional boxcars suitable for such purposes are normally provided with outlets therebeneath, which are in turn equipped with gates or doors such as a slide valve that may be easily opened when the contents of the boxcar are to be unloaded.

It is the most important object of the present invention to provide a seal that may be used in conjunction with the outlet gate of conventional boxcars for rendering the outlet gas-tight, all without necessity of modifying the gate itself or interfering with its normal operation.

It is another important object of the present invention to provide a seal within the outlet above the gate and disposed in a manner to permit opening of the latter Whereupon the seal -is easily broken by slitting a flexible panel of relatively lightweight material forming a part of the seal.

Another important object of the instant invention is to provide sealing means that includes complemental frames which hold the aforementioned panel in place by virtue of the way in which the frames are disposed in telescoping relationship.

7 Patented -A further object of the present invention is to provide continuous frame means which clamp the flexible panel in place at the marginal edge of the latter and hold the panel tightly stretched across the open-frames to prevent escape of the inert gas aforementioned.

In the drawing:

Fig. 1 is a vertical, cross-sectional view through the outlet of a railway boxcar-illustrating the gas-tight seal of the present invention operably mounted therein; and

Fig. 2 is an exploded perspective view partially broken away illustrating the three parts of the seal, namely, the two frames and the flexible panel.

The boxcar outlet illustrated in Fig.1 of the drawing is broadly designated by the numeral 10 and it is seen that the same is provided with a slide gate or valve 12 in the conventional manner, which gate 12 may be shifted to the open. position permitting flow of the products contained in the boxcar by force of gravity. The gate 12 is however, incapable of preventing escape of the carbon dioxide when the boxcar is employed to transport alfalfa I pellets as herein intially explained.

Pursuant to the present invention, therefore, there is provided a pair of substantially identical, complemental frames 14 and 16 that are preferably continuous. The polygonal configuration of the open frames 14 and 16 may, of course, be varied in accordance with the shape of the outlet 10 within which the seal is to be mounted.

Each of the frames 14 and 16 is transversely L-shaped, presenting therefore, a continuous vertical flange 18 and a continuous horizontal flange 20 for the frame 14. Similarly, the frame 16 is provided with a vertical flange 22 and a horizontal flange 24. In both instances the horizontal flanges are integral with, and extend outwardly from, the uppermost edges of the vertical flanges.

As seen in Fig. 1 of the drawing, the larger and outermost frame 14 is rigidly attached to the outlet 10 therewithin in any suitable manner such as by welding. Frame 16 is employed to hold a flexible panel 26 in place in the manner illustrated by Fig. 1. Any suitable material may be employed in making the panel 26 as long as the same is flexible and impervious to the flow of gas therethrough. Many plastic or vinyl products are today readily available on the open market for such purpose.

It is noted that the flange 18 is peripherally larger than the flange 22 and, therefore, when the panel 26 is laid upon the vertical flange 20 and the frame 16 moved into position, panel 26 will be held in position by the cooperative action of the two frames 14 and 16.

Fig. l of the drawing illustrates the way in which the marginal edge of the panel 26 is gripped between the flanges 18 and 22 by virtue of the fact that when frame 16 is in position, flange 18 completely surrounds flange 22. Under such conditions, the flange 24 overlaps the flange 20 and, therefore, a portion of the marginal edge of the panel 26 is held between flanges 20 and 24. The distance between the flanges 18 and 22 should, of course, be such as to actually grip the panel 26 and thereby, not only hold the latter in a taut condition but prevent slippage thereof from between the two frames 14 and 16. It is clear also from viewing Figs. 1 and 2 that the panel 26 completely closes the open continuous frames 14 and 16 when mounted in place as shown in Fig. 1.

When the contents of the boxcar are to be discharged through the outlet 10, it is but necessary to open the valve or gate 12 and thereupon, through use of any sharp instrument, slit the panel 26 and permit the flow of the material through the frames 14 and 16. When the seal is again to be placed in use, a new panel 26 is employed and the same can be easily and quickly mounted in place prior to refilling of the boxcar with the alfalfa pellets or the like.

Having thus described the invention what is claimed 3 t as new and desired to be secured by Letters Patent is:

In combination with a boxcar having an outlet opening, a seal for preventing the escape of gas through said opening, said seal comprising a first continuous frame adapted to be fixedly mounted within the opening; a secand continuous frame complemental to and removably telescoped within said first frame in, partial overlying rela tionship thereto; and a panel of flexible, gas impervious, easily frangible material held between said frames and adapted to close said opening, said panel having a marginal edge surrounding the second frame and gripped between the latter and the first frame, said frames being transversely L-shaped presenting a continuous vertical flange and a continuous horizontal flange, said horizontal flanges extending outwardly from the uppermost edges of said vertical flanges in a direction away from said opening, the vertical flanges being relatively telescoped and having the innermost portion of said marginal edge gripped therebetween, the horizontal flanges being in overlapped relationship and; having the outermost portion of said marginal edge held therebetween, said outermost portion of the edge completely overlying the horizontal flange of the first frame and extending beyond the horizontal flange of the second frame.

References Cited in the file of this patent. 

